Refraction corrected transmission ultrasound computed tomography for application in breast imaging

Purpose: We present an iterative framework for CT reconstruction from transmission ultrasound data which accurately and efficiently models the strong refraction effects that occur in our target application: Imaging the female breast. Methods: Our refractive ray tracing framework has its foundation in the fast marching method (FNMM) and it allows an accurate as well as efficient modeling of curved rays. We also describe a novel regularization scheme that yields further significant reconstruction quality improvements. A final contribution is the development of a realistic anthropomorphic digital breast phantom based on the NIH Visible Female data set. Results: Our system is able to resolve very fine details even in the presence of significant noise, and it reconstructs both sound speed and attenuation data. Excellent correspondence with a traditional, but significantly more computationally expensive wave equation solver is achieved. Conclusions: Apart from the accurate modeling of curved rays, decisive factors have also been our regularization scheme and the high-quality interpolation filter we have used. An added benefit of our framework is that it accelerates well on GPUs where we have shown that clinical 3D reconstruction speeds on the order of minutes are possible.

Accuracy of Tc-99m-sestamibi scintimammography for breast cancer diagnosis

Scintimammography using Tc-99m-sestamibi is a noninvasive and painless diagnostic imaging method that is used to detect breast cancer when mammography is inconclusive Because of the advantages of labeling v '7,ith Tc-99m-sestamibi and its high efficiency in detecting carcinomas, it is the most widespread agent for this purpose Its accumulation in the tumor has multifactorial causes and does not depend on the presence of architectural distortion or local or diffuse density variation in the breast The objective of tfiis study was to evaluate the accuracy of scintimammography 1 for detecting breast cancer One hundred and fifty-seven patients presenting 158 palpable and non-palpable breast nodules were evaluated Three patients were male and 154 were female, aged between 14 and 81 years All patients underwent scintimammography, and the nodule was subjected i to cytological or histological study, i e, the gold standard for diagnosing cancer One hundred and eleven malignant and 47 benign nodules were detected, with predominance of ductal carcinomas (n=94) and fibroadenoma/fibrocysiic condition (n=11/n=11), respectively The mean size was 3 11 cm (7-10 cm) among the malignant nodules and 2 07 cm among the benign nodules (0 5-10 cm) The sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 89, 89, 95, 78 and 89%, respectively Analysis on the histological types showed that the technique was more effective on tumors that were more aggressive, such as ductal carcinoma In this study, Tc-99m-sestamibi scintim immography was shown to be an important tool for diagnosing breast cancer when mammography was inconclusive

Physiotherapeutic stimulation: Early prevention of lymphedema following axillary lymph node dissection for breast cancer treatment

The aim of this study was to confirm the effectiveness of early physiotherapeutic stimulation for lymphatic flaw progression in patients with breast cancer undergoing axillary dissection This was a randomized experimental study oil 22 patients who underwent lymphoscintigraphy in their arms on two different occasions, firstly without stimulation and secondly after randomization into two groups without physiotherapeutic stimulation (WOPS, n=10) and with physiotherapeutic stimulation (WPS, n=12) The lymphoscintigraphy scan was performed with (99m)Tc-phytate administered into the second interdigital space of the hand, ipsilaterally to the dissected axilla, in three phases dynamic, static, and delayed whole body imaging Physiotherapeutic stimulation was earned out using Foldi's technique In both groups, images from the two examinations of each patient were compared Flow progression was considered positive when, on the second damnation, the radiopharmaceutical reached areas more distant from the injection site Statistical analysis was used to evaluate frequencies, percentages and central trend measurements, and non-parametric tests were conducted Descriptive analysis showed that the WPS and WOPS groups were similar M terms of mean age, weight, height, body mass index and number of lymph nodes removed There were statistically significant associations between physiotherapeutic stimulation and radiopharmaceutical progression at all three phases of the study (p < 0 0001) Early physiotherapeutic stimulation in beast cancer patients undergoing radical axillary dissection is effective, and can therefore be indicated as a preventive measure against lymphedema

Preoperative upper limb lymphatic function in breast cancer surgery

Objective: To describe the preoperative upper limb lymphoscintigraphic pattern in women with breast cancer. Methods: Thirty-seven patients undergoing lymphoscintigraphy within 30 days of surgery were investigated. Lymphoscintigraphic studies of 37 upper limbs ipsilateral to surgery and 32 contralateral upper limbs were performed. The examination protocol consisted in obtaining static images of the upper limb in semi-flexion after 10 minutes, and 1 and 2 hours after subcutaneous injection of 1 mCi (37 MBq) of Tc-99m-dextran in the dorsum of the hand. The velocity of axillary lymph node visualization (I, visible at 10 minutes; II, 1 hour; III, 2 hours; and IV, invisible) and degree (intensity) of nodal uptake (a, marked; b, moderate; c,mild; and d, absent) were analyzed. Results: Optimal lymphatic functional pattern (Ia) was observed in four (11%) patients, in the ipsilateral upper limb, and six (19%), in the contralateral upper limb. Worse condition was observed in three (8%) patients (IVd) in the ipsilateral upper limb and two (6%) patients in the contralateral upper limb. The remaining patients showed intermediate states of velocity and uptake intensity. Conclusion: This study found relevant changes in preoperative lymphoscintigraphy, demonstrating preexisting functional differences in the lymphatic system. © 2011 Elsevier Editora Ltda.

Stress analysis in oral obturator prostheses: Imaging photoelastic

Maxillary defects resulting from cancer, trauma, and congenital malformation affect the chewing efficiency and retention of dentures in these patients. The use of implant-retained palatal obturator dentures has improved the self-esteem and quality of life of several subjects. We evaluate the stress distribution of implant-retained palatal obturator dentures with different attachment systems by using the photoelastic analysis images. Two photoelastic models of the maxilla with oral-sinus-nasal communication were fabricated. One model received three implants on the left side of the alveolar ridge (incisive, canine, and first molar regions) and the other did not receive implants. Afterwards, a conventional palatal obturator denture (control) and two implant-retained palatal obturator dentures with different attachment systems (O-ring; bar-clip) were constructed. Models were placed in a circular polariscope and a 100-N axial load was applied in three different regions (incisive, canine, and first molar regions) by using a universal testing machine. The results were photographed and analyzed qualitatively using a software (Adobe Photoshop). The bar-clip system exhibited the highest stress concentration followed by the O-ring system and conventional denture (control). Images generated by the photoelastic method help in the oral rehabilitator planning. © 2013 SPIE.

Pesquisa de segunda neoplasia em boca e orofaringe em pacientes portadores de carcinoma espinocelular (CEC) de esôfago, boca e orofaringe através de narrow band imaging (NBI)

Pós-graduação em Pesquisa e Desenvolvimento (Biotecnologia Médica) - FMB

Evaluation of clinical, ultrasonographic and hysteroscopic parameters in the differentiation of endometrial polyps and cancer of endometrium

Study Objective: To evaluate the diagnostic accuracy of transvaginal ultrasound and office hysteroscopy in the differentiation between endometrial polyps and endometrial adenocarcinoma. Design: This is a prospective 100 women longitudinal study, 24 to 80 years, submitted to hysteroscopic polypectomy (n = 80) or surgery due to endometrial adenocarcinoma (n = 20), from january 2010 to December 2011. Clinical, ultrasonographic and hysteroscopic parameters were analyzed and compared with histopathologic find. Statistical analysis were performed utilizing the Tukey, Kruskal-Wallis, Dunn and Mann-Whitney test, with a confidence interval of 95% and p\0, 05 statiscally significant. Setting: Botucatu Medical School. Intervention: Prospective analysis of clinical, ultrasonographic and hysteroscopic parameters in patients with diagnosis suspected of endometrial polyps and adenocarcinoma of endometrium were performed. According to the diagnosis, hysteroscopic polypectomy or pan hysterectomy with lymph node sampling was realized. After the surgery and histopathological study, statistical analysis of parameters was performed and the results were compared between groups. It was Research Ethics Committee approved. Measurements and Main Results: There were no differences between age, BMI, menopause, TH use and associated diseases among groups. The main symptom of endometrial cancer was the postmenopausal bleeding, affecting 84,2% of women against 34,8% of polypectomy group. The majority of women with endometrial polyps were asymptomatic. Transvaginal ultrasonography showed no ability to differentiate cases of endometrial cancer compared with the cases of endometrial polyps, considering the presence of endometrial thickness and blood flow on color Doppler. Office hysteroscopy showed significant changes in 75% of the adenocarcinoma cases, especially the presence of diffuse hypervascularity with atypical vessels. Conclusion: Still remains an inability to establish clinical parameters and reliable ultrasound imaging to differentiate endometrial polyps and cancer of endometrium. Attention should be given to hysteroscopic exams presenting diffuse endometrial hypervascularization with architectural distortion of the vessels. The recommendation of our service remains the systematic removal of all endometrial polyps.

Angiotensin II Facilitates Breast Cancer Cell Migration and Metastasis

Breast cancer metastasis is a leading cause of death by malignancy in women worldwide. Efforts are being made to further characterize the rate-limiting steps of cancer metastasis, i.e. extravasation of circulating tumor cells and colonization of secondary organs. In this study, we investigated whether angiotensin II, a major vasoactive peptide both produced locally and released in the bloodstream, may trigger activating signals that contribute to cancer cell extravasation and metastasis. We used an experimental in vivo model of cancer metastasis in which bioluminescent breast tumor cells (D3H2LN) were injected intra-cardiacally into nude mice in order to recapitulate the late and essential steps of metastatic dissemination. Real-time intravital imaging studies revealed that angiotensin II accelerates the formation of metastatic foci at secondary sites. Pre-treatment of cancer cells with the peptide increases the number of mice with metastases, as well as the number and size of metastases per mouse. In vitro, angiotensin II contributes to each sequential step of cancer metastasis by promoting cancer cell adhesion to endothelial cells, trans-endothelial migration and tumor cell migration across extracellular matrix. At the molecular level, a total of 102 genes differentially expressed following angiotensin II pretreatment were identified by comparative DNA microarray. Angiotensin II regulates two groups of connected genes related to its precursor angiotensinogen. Among those, up-regulated MMP2/MMP9 and ICAM1 stand at the crossroad of a network of genes involved in cell adhesion, migration and invasion. Our data suggest that targeting angiotensin II production or action may represent a valuable therapeutic option to prevent metastatic progression of invasive breast tumors.

IS A VISIBLE (HYPOECHOIC) LESION AT BIOPSY AN INDEPENDENT PREDICTOR OF PROSTATE CANCER OUTCOME?

The aim of this study was to evaluate the prognostic implications of the sonographic appearance of prostate cancers. All patients with biopsy-proven prostate cancer between January 2003 and July 2004 (and at least 5 years of follow-up) were selected retrospectively. After exclusions, 101 patients constituted our study population and were divided into isoechoic (or nonvisible) and hypoechoic (or visible) lesion. The clinical outcomes of these two groups were compared. The outcomes for the two groups were significantly different (p < 0.01). For nonvisible lesions, 37 of the 41 patients (90.2%) had no disease relapse and 2 (4.9%) had biochemical failure. For the visible lesions, 37 of the 60 (61.6%) patients were free of recurrence, 7 (11.7%) had systemic metastases and 10 (16.7%) died of complications related to prostate cancer. Our data show that patients with nonvisible prostate cancer had significantly better outcomes than patients with visible lesions during a five-year period of evaluation. (E-mail: fmuglia@fmrp.usp.br) (c) 2012 World Federation for Ultrasound in Medicine & Biology.

Optimal Timing for Assessment of Tumor Response to Neoadjuvant Chemoradiation in Patients With Rectal Cancer: Do All Patients Benefit From Waiting Longer Than 6 Weeks?

Purpose: To estimate the metabolic activity of rectal cancers at 6 and 12 weeks after completion of chemoradiation therapy (CRT) by 2-[fluorine-18] fluoro-2-deoxy-D-glucose-labeled positron emission tomography/computed tomography ([18 FDG] PET/CT) imaging and correlate with response to CRT. Methods and Materials: Patients with cT2-4N0-2M0 distal rectal adenocarcinoma treated with long-course neoadjuvant CRT (54 Gy, 5-fluouracil-based) were prospectively studied (ClinicalTrials. org identifier NCT00254683). All patients underwent 3 PET/CT studies (at baseline and 6 and 12 weeks fromCRT completion). Clinical assessment was at 12 weeks. Maximal standard uptakevalue (SUVmax) of the primary tumor wasmeasured and recorded at eachPET/CTstudy after 1 h (early) and3 h (late) from 18 FDGinjection. Patientswith an increase in early SUVmax between 6 and 12 weeks were considered " bad" responders and the others as "good" responders. Results: Ninety-one patients were included; 46 patients (51%) were "bad" responders, whereas 45 (49%) patients were " good" responders. " Bad" responders were less likely to develop complete clinical response (6.5% vs. 37.8%, respectively; PZ. 001), less likely to develop significant histological tumor regression (complete or near-complete pathological response; 16% vs. 45%, respectively; PZ. 008) and exhibited greater final tumor dimension (4.3cmvs. 3.3cm; PZ. 03). Decrease between early (1 h) and late (3 h) SUVmax at 6-week PET/CTwas a significant predictor of " good" response (accuracy of 67%). Conclusions: Patients who developed an increase in SUVmax after 6 weeks were less likely to develop significant tumor downstaging. Early-late SUVmax variation at 6-week PET/CT may help identify these patients and allow tailored selection of CRT-surgery intervals for individual patients. (C) 2012 Elsevier Inc.

ORAL MUCOSITIS PREVENTION BY LOW-LEVEL LASER THERAPY IN HEAD-AND-NECK CANCER PATIENTS UNDERGOING CONCURRENT CHEMORADIOTHERAPY: A PHASE III RANDOMIZED STUDY

Purpose: Oral mucositis is a major complication of concurrent chemoradiotherapy (CRT) in head-and-neck cancer patients. Low-level laser (LLL) therapy is a promising preventive therapy. We aimed to evaluate the efficacy of LLL therapy to decrease severe oral mucositis and its effect on RT interruptions. Methods and Materials: In the present randomized, double-blind, Phase III study, patients received either gallium-aluminum-arsenide LLL therapy 2.5 J/cm(2) or placebo laser, before each radiation fraction. Eligible patients had to have been diagnosed with squamous cell carcinoma or undifferentiated carcinoma of the oral cavity, pharynx, larynx, or metastases to the neck with an unknown primary site. They were treated with adjuvant or definitive CRT, consisting of conventional RT 60-70 Gy (range, 1.8-2.0 Gy/d, 5 times/wk) and concurrent cisplatin. The primary endpoints were the oral mucositis severity in Weeks 2, 4, and 6 and the number of RT interruptions because of mucositis. The secondary endpoints included patient-reported pain scores. To detect a decrease in the incidence of Grade 3 or 4 oral mucositis from 80% to 50%, we planned to enroll 74 patients. Results: A total of 75 patients were included, and 37 patients received preventive LLL therapy. The mean delivered radiation dose was greater in the patients treated with LLL (69.4 vs. 67.9 Gy, p = .03). During CRT, the number of patients diagnosed with Grade 3 or 4 oral mucositis treated with LLL vs. placebo was 4 vs. 5 (Week 2, p = 1.0), 4 vs. 12 (Week 4, p = .08), and 8 vs. 9 (Week 6, p = 1.0), respectively. More of the patients treated with placebo had RT interruptions because of mucositis (6 vs. 0, p = .02). No difference was detected between the treatment arms in the incidence of severe pain. Conclusions: LLL therapy was not effective in reducing severe oral mucositis, although a marginal benefit could not be excluded. It reduced RT interruptions in these head-and-neck cancer patients, which might translate into improved CRT efficacy. (C) 2012 Elsevier Inc.

Adjuvant chemoradiotherapy after d2-lymphadenectomy for gastric cancer: the role of n-ratio in patient selection. results of a single cancer center

Background: Adjuvant chemoradiotherapy is part of a multimodality treatment approach in order to improve survival outcomes after surgery for gastric cancer. The aims of this study are to describe the results of gastrectomy and adjuvant chemoradiotherapy in patients treated in a single institution, and to identify prognostic factors that could determine which individuals would benefit from this treatment. Methods: This retrospective study included patients with pathologically confirmed gastric adenocarcinoma who underwent surgical treatment with curative intent in a single cancer center in Brazil, between 1998 and 2008. Among 327 patients treated in this period, 142 were selected. Exclusion criteria were distant metastatic disease (M1), T1N0 tumors, different multimodality treatments and tumors of the gastric stump. Another 10 individuals were lost to follow-up and there were 3 postoperative deaths. The role of several clinical and pathological variables as prognostic factors was determined. Results: D2-lymphadenectomy was performed in 90.8% of the patients, who had 5-year overall and disease-free survival of 58.9% and 55.7%. The interaction of N-category and N-ratio, extended resection and perineural invasion were independent prognostic factors for overall and disease-free survival. Adjuvant chemoradiotherapy was not associated with a significant improvement in survival. Patients with node-positive disease had improved survival with adjuvant chemoradiotherapy, especially when we grouped patients with N1 and N2 tumors and a higher N-ratio. These individuals had worse disease-free (30.3% vs. 48.9%) and overall survival (30.9% vs. 71.4%). Conclusion: N-category and N-ratio interaction, perineural invasion and extended resections were prognostic factors for survival in gastric cancer patients treated with D2-lymphadenectomy, but adjuvant chemoradiotherapy was not. There may be some benefit with this treatment in patients with node-positive disease and higher N-ratio.

Nanoassisted Laser Desorption-Ionization-MS Imaging of Tumors

The ability of nanoassisted laser desorption-ionization mass spectrometry (NALDI-MS) imaging to provide selective chemical monitoring with proper spatial distribution of lipid profiles from tumor tissues after plate imprinting has been tested. NALDI-MS imaging identified and mapped several potential lipid biomarkers in a murine model of melanoma tumor (inoculation of B16/F10 cells). It also confirmed that the in vivo treatment of tumor bearing mice with synthetic supplement containing phosphoethanolamine (PHO-S) promoted an accentuated decrease in relative abundance of the tumor biomarkers. NALDI-MS imaging is a matrix-free LDI protocol based on the selective imprinting of lipids in the NALDI plate followed by the removal of the tissue. It therefore provides good quality and selective chemical images with preservation of spatial distribution and less interference from tissue material. The test case described herein illustrates the potential of chemically selective NALDI-MS imaging for biomarker discovery.

Analysis by MRI of Residual Tumor After Radiofrequency Ablation for Early Stage Breast Cancer

OBJECTIVE. The objective of our study was to evaluate the effectiveness of MRI in the detection of possible residual lesions after radiofrequency ablation (RFA) in the treatment of breast cancer. SUBJECTS AND METHODS. We prospectively evaluated 14 patients who had undergone ultrasound-guided core biopsies diagnostic of invasive ductal carcinoma (IDC; range of diameters, 1.0-3.0 cm) and then ultrasound-guided percutaneous RFA with sentinel node biopsy as the primary treatment. Breast MRI was performed 1 week before RFA to evaluate tumor extension and again 3 weeks after RFA to verify the presence of possible residual lesions. Conventional surgical resection of the tumors was performed 1 week after RFA. The MRI findings were compared with histopathologic analyses to confirm the presence or absence of residual tumor. RESULTS. There was no residual enhancement in seven lesions on the postablation breast MRI scans. These findings were confirmed by negative histopathologic findings in the surgical specimens. The MRI scans of five patients showed small areas of irregular enhancement that corresponded to residual lesions. In the two remaining patients, we observed enhancement of almost the entire lesion, indicating that RFA had failed. CONCLUSION. Breast MRI is effective in detecting residual lesions after RFA in patients with IDC.